Vibrator



April 2, 1935. I E. H. LICHTENBERG VI BRATOR Filed Nov. 13, 1933 iatented Apr. ;2, 1935 PATENT oFFlcs i VIBRATOR i Erich n. momenten, Milwaukee, wis., signerto Koehrin;r Company, Milwaukee, Wis., a corporation Application November 13, 1933, Serial No. 697.828

3 Claims.

This invention relates to concrete mixers, particularly the type embodying a rotatable mixing drum and a skip for charging the same. The invention has to do with -a means for vibrating the skip to effect as near as possible a complete discharge of all of the dry aggregates into the mixing drum. One object of this invention is to provide a skip vibrating means which is very simple in construction and which may be operated by the main power drive of the mixer with a minimum of additional parts. Another object of the invention is to provide a skip vibrating means that will operate only when the skip is in discharging position, and an advantageous feature of the invention resides in the fact that the vibrating means may be rendered inoperative if so desired, so that the skip will not be vibrated when unloaded. It is of note to mention that through my improved arrangementI a vertical vibration will be imparted to the skip so that all of the contents of the skip to be vibrated therefrom will move down the skip in a vertical direction into the mixing drum as distinguished over the vibrating mechanisms that operate in a horizontal direction and do not effect a complete discharge of all of the aggregates adhering to the sides and bottom of the skip.

Other objects and advantageous features of this invention will be found in the accompanying drawing and detailed description, wherein like characters of reference designate like parts, and wherein- Figure 1 is a plan view of a complete mixing machine disclosing a preferred embodiment of my invention.

Figure 2 is a detail of the vibrating mechanism.

Figure 3 is a top plan view of the mechanism shown in Figure 2.

Figure 4 is a fragmentary detail of one of the skip bearlngs.

Figure 5 is a fragmentary detail of the rocker arm showing a slightly modified form of guide therefor.

With reference to the drawing, I have-shown in Figure 1 a conventional type of mixing machine which includes a frame A supported or wheels B, the frame carrying a conventional type of mixing drum C having a charging opening D for receiving aggregates which are delivered thereto by a skip E supported by uprights F in spaced bearings I.

Essentially the apparatus for supporting the skip consists in a crossbar l joumaled at its ends in the'bearings I which are each provided with elongated slots 2 in a vertical direction for accommodating the end of the shaft so that the shaft may be moved up and down in-a vertical plane as will be observed -in Figure 4, so that the skip E may also be so moved. This will be taken up hereinafter in connection with the 5 vibrating mechanism.

The devices for lowering and raising the skip include the. prime mover H Which operates a cable and pulley arrangement 5 of conventional design and operable in a well known manner. 10 However, the lower pulley 6 is mounted on a horizontal shaft 'I on the frame rotated through sprocket and chain mechanisms, the chain 8 of which is shown, the shaft being supported at its lends in the usual bearings 9. 15

The skip vibrating mechanism is driven from the shaft 'l by means of a cam I 0 mounted thereon for rotation with the shaft. Vibratory motion is transmitted to the skip through the me- I dium of a rocker arm 12 pivoted at its mid- 20 point on an upstanding bracket i3 supported on a frame horizontally. The power arm side of the lever |2 is provided with a roller H that engages with the cam, whereas the work arm side of the lever pivotally mounts an impact member i5 having an impact face IG. Through the pivotal mounting of this member, it can be swung from full line to dotted. line position, Figure 2, for a purpose to be later brought out. Reference may be had to Figure 3 which shows the offset relation of the power side of the lever to the work arm side in order to properly clear certain parts of the mixer assembly. On the power arm side of the lever is also an ear I'I extending normally to the lever, provided With a slotted opening l'l' for the reception of a bolt |8 mounting a resilient coil spring 20 between the said ear and bolt head for urging the power arm side of the lever downwardly, and acting as a buifer spring for cushioning the return 40 movement of the rocking arm. This bolt is threaded into the frame and is provided with the nut and lock nut assembly 2i for locking the bolt l8.

It will be observed in Figure 2 that the .shaft I is provided with an oifset portion 22 extending beyond the general plane of the shaft and in such position that it may be moved into the zone of the impact member i5 upon raising of the skip, and which, when the skip is lowered, moves out of engagement with said impact member. So much for the apparatus per se, albeit it is to be pointed out that if desired the bracket 13 supporting the rocker arm may be adjustable for height through an arrangement such as that in Figure 1 wherein the bracket is slottedasatllandboltedtotheframathemanner inwhichthesamemaybeadiustedbeingperfectly obvious.

'I'o describe the operation of this device. it is suiilcient to point out that the skip may be raised and lowered through the pulley and cable arrangement disclosed at I. When the skip is raised. the abutment member 22 is brought around into the zone of the impact member Il with the impact face il against the member 22. At this time the bearings in the shaft i lie at the bottom of the slot, and as shown in Figure 4 and the skip is in a substantially vertical position. Rotation of the shaft 1 tums the cam member, bringing the cam faces, into engagement with the roller ll by virtue of which a rocking movement is imparted to the lever II. This action eifects the vertical reciprocation of the skip, the bearings of the shaft I reoiproeating in the slot 2. Where this motion is rapid. a vibration is imparted to the skip in a vertical direction suilicient to shake out all ofxthe loose aggregates and eiIect the discharge thereof into the loading oriilce of the drum. If for some reason or other it is not desirable to shake the skip, the impact member II may be swung to dotted line position. This of course prevents engagement between the impact face i. and the abutment member -22 and no vibration is imparted to the skip. In conclusion, the power arm side of the lever l2 may bear a ratio two to one to the work arm side or any ratio desired may be set up to vary the mechanical advantagein accordance with the type of machine employed; the prime mover, and the weight of the skip.

Referring to Figure 5, I have shown therein a slightly modified form of guide for the rocker arm i2 -whereinthe spring 20 is omitted and the function of the bolt IB is to guide the rocker arm. i

Although I have shown a preferred form of my invention, several changes may occur to those skilled in the art for subserving the same end without departing from the spirit and scope of this invention, and I do not care to be limited to the exact disclosure except as indicated in the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States, is-

1. In combination with a concrete mixing machine having a skip oapable of being moved in a vertical direction and raised to discharging position, a mechanism for imparting movement in a vertical direction to said skip when so raised, whichincludes a driven cam, a rocker arm pivoted intermediate its ends, an impact member pivotally connected to said rocker arm, a shaft to which said skip is connected, said shaft having an abutment thereon for cooperation with said impact member, said impact member being movable into and out of the path of said abutment member. I

2. In combination with a concrete m ixing mschine having a skip capable of being moved in a vertical direction and raised to discharging position, a mechanism for imparting movement in a vertical direction to said skip when so raised, which includes a driven cam, a rocker arm plvoted intermediate its ends, an impact member pivotally connected to said rocker arm, a sh-aft to which said skip is connected, said shaft having an abutment thereon for cooperation with said impact member, said shaft being movable to bring the abutment member into and out of cooperative relation' with the impact member, said impact member being movable into and out of the path of the abutment member.

3. In a mechanism for vibrating a skip, a lever pivoted at its midpoint, means for rocking said lever about its pivot, and an impact member pivotally mounted on the said lever and movable about an axis transversely of the lever. so that it may be shifted into a position for vibrating cooperation with the skip and into a position in which it is inactive in respect to the skip.

ERICH H. LICH'I'ENBERG. 

